Pheromone-based decision support tools for management of <Emphasis Type="Italic">Halyomorpha halys</Emphasis> in apple orchards: development of a trap-based treatment threshold

The invasive brown marmorated stink bug, Halyomorpha halys (Stål), has become a serious pest in mid-Atlantic apple orchards. Because no decision support tools exist for H. halys management, calendar-based insecticide applications have been the only successful technique for mitigating H. halys injury in orchards. Following the identification of the two-component aggregation pheromone of H. halys, we conducted a study to determine whether biological information generated by traps baited with this pheromone and pheromone synergist could be used to make management decisions. In this study, experimental apple orchards were treated with a H. halys-targeted insecticide only when a predetermined cumulative threshold of either 1, 10, or 20 adults per trap was reached. Once threshold was reached, two alternate row middle sprays 1 week apart were triggered and the threshold was reset. For comparison, some orchards were also subjected to a weekly alternate row middle spray or left untreated as controls. At harvest, significantly less fruit injury was observed when treated weekly or using a threshold of 1 or 10 H. halys adults per trap to trigger insecticide applications. Orchards treated using a cumulative threshold of 20 adults per trap or when left unsprayed had significantly higher fruit injury. In addition, insecticide applications were reduced by 40% using a threshold of 10 adults per trap. Our results suggest that baited pheromone traps can be used as decision support tools to trigger insecticide applications when needed to mitigate risk and effectively manage H. halys in apple orchards.     

Morpho‐physical Recording of Bovine Conceptus (Bos indicus) and Placenta from Days 20 to 70 of Pregnancy

The study is based on 141 pregnant Bos indicus cows, from days 20 to 70 post‐insemination. First, special attention was given to the macroscopically observable phenomena of attachment of the conceptus to the uterus, i.e. the implantation, from about days 20 to 30 post‐insemination up to day 70, and placentome development by growth, vascularization and increase in the number of cotyledons opposite to the endometrial caruncles. Secondly, as for the conceptuses, semiquantitative, statistical analyses were performed of the lengths of chorio‐allantois, amnion and yolk sac; and the different parts of the centre and two extremes of the yolk sacs were also analysed. Thirdly, the embryos/foetuses corresponding to their membranes were measured by their greatest length and by weight, and described by the appearance of external developmental phenomena during the investigated period like neurulation, somites, branchial arcs, brain vesicles, limb buds, C‐form, pigmented eye and facial grooves. In conclusion, all the data collected in this study from days 20 to 70 of bovine pregnancy were compared extensively with corresponding data of the literature. This resulted in an ‘embryo/foetal age‐scale’, which has extended the data in the literature by covering the first 8 to 70 days of pregnancy. This age‐scale of early bovine intrauterine development provides model for studies, even when using slaughtered cows without distinct knowledge of insemination or fertilization time, through macroscopic techniques. This distinctly facilitates research into the cow, which is now being widely used as ‘an experimental animal’ for testing new techniques of reproduction like in vitro fertilization, embryo transfer and cloning.     

Efficacy of a combined paste formulation of praziquantel/febantel against immature Echinococcus granulosus and immature Echinococcus multilocularis

A combined paste formulation of praziquantel (1 mg/kg of body wt)/febantel (10 mg/kg) given for 3 consecutive days gave 100% clearance of immature Echinococcus granulosus and E multilocularis in experimentally infected dogs. The formulation was extremely convenient to administer. Adverse reactions were not noted in the treated animals.     

Pine needle abortion in cattle: associated changes in serum cortisol, estradiol and progesterone

Nineteen spring-calving cows were used in an experiment to study the effect of feeding pine needles on incidence of premature parturitions (abortions) and the associated changes in serum cortisol, estradiol-17 beta and progesterone. The study was conducted over 2 years (1983, seven cows fed pine needles and three controls; 1984, six cows fed pine needles and three controls). Experimental feeding started at an average of 250 d of gestation and continued until parturition. Daily blood samples were taken from the start of feeding through 2 to 4 d after parturition. Feeding pine needles shortened gestation by 16 d and induced a premature normal rise in cortisol and estradiol-17 beta associated with parturition. Cortisol concentrations were also high at the beginning of the bleeding period and remained higher in pine needle-fed cows. An abrupt rise in progesterone concentration occurred after the start of pine needle feeding which then decreased sharply for 7 to 8 d before parturition and did not decrease to control concentrations until after parturition. We conclude that feeding pine needles to pregnant cows in late gestation causes abortions and that these abortions are directly caused by or are associated with changes in steroid metabolism.     

Disposition of fenbendazole in the rabbit

The disposition of fenbendazole was studied in rabbits following either oral or intravenous administration. The major metabolites appearing in plasma were fenbendazole sulphoxide (oxfendazole) and fenbendazole sulphone. Calculation of the total urinary and faecal elimination of the drug and of its known metabolites showed that only 40 per cent of the dose was recovered after oral dosing; 29.7 per cent after an intravenous dose. The sulphoxide and sulphone were minor elimination products. The major excretory metabolite was p-hydroxyfenbendazole.     

Specific effects of blood plasma from beef cows fed pine needles during late pregnancy on increasing tone of caruncular arteries in vitro.

Consumption of Ponderosa pine needles by cows during late pregnancy results in the premature delivery of viable calves. Previous observations made at necropsy suggested that vascular insufficiency in the caruncular bed was associated with this induced parturition. The present studies used the perfused caruncular arterial bed of an isolated bovine placentome to determine whether blood plasma collected from cows fed pine needles contained a vasoactive factor(s). Changes in caruncular arterial tone (i.e., long-term changes in vessel diameter) and phasic contractility (i.e., transient reductions in vessel diameter) were evaluated. Tone was quantified as the pressure exerted against a constant intraluminal flow and as the force of contraction during K(+)-stimulated depolarization of membranes. Phenylephrine, an alpha 1-adrenergic agonist, was used to stimulate a phasic contractile response. Jugular blood was collected from beef cows fed pine needles (n = 4) or a control diet (n = 4), during the last 3 d of gestation, and plasma was used for two studies. In Study 1, placentomes were perfused with decreasing dilutions (1:150 to 1:40) of plasma pooled over the last 3 d of pregnancy from cows fed pine needle or control diets. Caruncular arterial perfusion pressures and responses to K+ progressively increased (P less than .05) with decreasing dilutions of plasma from cows fed pine needles, and responses to phenylephrine remained constant. Caruncular arterial perfusion pressures and responses to K+ and phenylephrine remained constant during perfusion of plasma from cows fed the control diet. In Study 2, the changes in vasoactivity of plasma (1:60 dilution) from cows fed pine needles was evaluated during the last 3 d of pregnancy.(ABSTRACT TRUNCATED AT 250 WORDS)     

Pharmacokinetics and metabolism of fenbendazole in channel catfish

Fenbendazole (FBZ) was administered intravenously (1 mg/kg) and orally (5 mg/kg) to catheterized, confined channel catfish. Blood samples were collected for 72 h, and resulting FBZ plasma concentrations were pharmacokinetically modelled. Following intravenous administration t1/2 was 0.51 h, t1/2 was 16.8 h, body clearance (C1b) was 0.0598 L/kg/h, and Vd (area) was 1.45 L/kg. After oral administration the t1/2 (abs) was 1.47 h, the t1/2 was 20.1 h, and the tlag was 0.1 h.Following oral administration of 5 mg FBZ/kg body weight, the following tissues and body fluids were sampled for concentrations of FBZ, oxfendazole (FBZ-SO), sulphone metabolite (FBZ-SO₂) and hydroxy metabolite (FBZ-OH): liver, posterior kidney, fat, muscle, bowel contents and urine. Fenbendazole was detected in the highest concentrations in abdominal fat, whereas oxfendazole was found primarily in the kidney, liver and abdominal fat. The sulphone metabolite was detected only in urine and bowel contents, while the hydroxy metabolite was found most often in the liver and abdominal fat samples.     

Gastrointestinal ultrasonography in normal adult ponies

The objective of this study was to determine the characteristics based on ultrasonographic examination of the stomach, duodenum, jejunum, cecum, and peritoneal fluid in normal adult ponies. Abdominal ultrasonographic examination was performed in nine unsedated standing ponies. The duodenum was examined at three sites and the jejunum in 12 regions. Wall thickness, contractility, distention, and luminal contents were recorded. Stomach wall thickness and location, cecal wall thickness, and peritoneal fluid location and character were recorded. Statistical analysis was performed. Wall thicknesses (in cm) were 0.431 +/- 0.069 for the stomach, 0.188 +/- 0.033 for the duodenum (at all sites), 0.195 +/- 0.031 for the jejunum (at all regions), and 0.179 +/- 0.031 for the cecum. Duodenal contractions per minute were 3.78 +/- 1.10. The stomach spanned 5.14 +/- 0.9 intercostal spaces, with the 8th intercostal space being the most cranial and the 15th intercostal space being the most caudal space through which the stomach was identified. It was possible to identify the jejunum in all ponies dorsal to the left dorsal colon and from the ventral abdominal wall. Peritoneal fluid was identified in six ponies. Peritoneal fluid was usually seen transiently and most commonly in the ventral aspect of the abdominal cavity or around the duodenum. Overall, the ponie's abdominal ultrasonographic examinations revealed wall thicknesses that were less than the published normal ranges for horses. It appears that ponies may have increased duodenal contractility than horses and that the conformation of ponies may change the locations for imaging the stomach.